The present invention relates to a safety device for a foldable two-section chute system of a concrete mixing truck. In particular, the present invention relates to a blocking member positionable between adjacent ends of two chute sections when the chute system is transitioning from a folded position to an unfolded position.
Concrete mixing trucks are a common sight on the roads and at construction sites. FIG. 1 depicts a typical concrete mixing truck 10 used to transport, mix, and pour concrete. The concrete mixing truck 10 comprises a rotatable drum 12 connected to the frame of the truck 10. The rotatable drum 12 has an outlet 14 directed towards a two-section chute system 16 comprised of a first chute section 18 and a second chute section 20. The first chute section 18 has a first end 22 and a second end 24. The first end 22 of the first chute section 18 is pivotally connected to the concrete mixing truck 10. The second end 24 of the first chute section 18 is connected to a hydraulic cylinder 26 that is attached to the frame of the truck 10. The second chute section 20 has a first end 28 opposing the second end 24 of the first chute section 18. The first chute section 18 and the second chute section 20 are attached by a pivotal connection 30 located at top edges 32, 34 of chute sections 18, 20, respectively, adjacent to the second end 24 of the first chute section 18 and the first end 28 of the second chute section 20.
The two chute sections 18, 20 are traditionally capable of being in either a folded position or an unfolded position. During transport, the chute sections 18, 20 are placed in the folded position with the second chute section 20 resting on top of the first chute section 18 as shown in FIG. 1. When the concrete is ready for pouring, the second chute section 20 is rotated about the pivotal connection 30 until the second end 24 of the first chute section 18 and the first end 28 of the second chute section 20 make contact. The hydraulic cylinder 26 aligns the unfolded two-section chute system 16 with the desired location for pouring concrete. Concrete in the rotatable drum 12 is moved through the outlet 14 onto the chute system 16.
One of the problems related to the two-section chute system of concrete mixing trucks occurs when the second chute section is in the process of unfolding. To move from the folded position to the unfolded position, the second chute section is initially manually rotated to an angle sufficient to allow the second chute section to continue rotating by gravity into the final unfolded position. The two-section chute system is in the final unfolded position when the opposing end of the second chute section abuts the opposing end of the first chute section and the second chute section is forced to stop its rotation. The weight of the second chute section, combined with the momentum of the second chute section from the gravitational rotation, can cause injury to a person working alongside a concrete mixing truck in the event the person has a body part located between the opposing edges of the two chute sections. If a person is unaware that the second chute section is being unfolded, the person may not be able to remove the body part from the contact area of the two chute sections in time to avoid injury. It is thus desirable to improve the safety of two-section chute systems.
The spacing device of the present invention prevents unintended contact between two pivotally attached chute sections of a concrete mixing truck, where the first chute section comprises an annular flange adjacent to a second end of the first chute section and the second chute section comprises an arcuate edge configured to contact the annular flange of the first chute section. The spacing device comprises a mounting flange connected adjacent to the second end of the first chute section and a blocking member connected to the mounting flange. The blocking member comprises a contact surface that is spaced from the annular flange and positioned to contact a portion of the arcuate edge of the second chute section when the blocking member is in a blocking position.